The invention relates to an open roof construction with lower closing elements such as sun screens.
Such an open roof construction is for example known from EP-B-0 338 614. In this prior art open roof construction a sliding shoe is slidably guided on the lower closing element, in this case a sun screen. The sliding shoe is spring-loaded both in an outward direction and in a direction perpendicularly to the lower closing element. Although this construction ensures that the suspension of the lower closing element is to a large extent rattle-free, rattling may nevertheless develop when play occurs in the vertical direction of the guide groove.
The object of the present invention is to provide an improved open roof construction in regards to this point.
In order to accomplish that objective, the open roof construction according to the invention, in a first embodiment thereof, includes two sliding shoes that are connected to the lower closing element on both sides of a fixing point to said lower closing element the sliding shoes are each biased by an associated spring member, while means are provided by which said spring members are loaded in a vertical direction from said fixing point.
Any play in the vertical direction of the guide groove is thus eliminated. The two spring members are so loaded with respect to the fixing point that hardly any forces will be exerted on the lower closing element, if at all.
In a first embodiment of the invention, the open roof construction means for loading the sliding shoes in the vertical direction are provided with an element provided at the fixing point, by means of which said spring members are loaded in vertical direction.
In a practical embodiment, two sliding shoes are combined in one unit, while the mounting element is fixed to the lower closing element, wherein the element for loading the spring members consists of an auxiliary sliding shoe, which is formed on the mounting element, on a side remote from the lower closing element where the spring members abut, and which is capable of engaging in the associated guide groove, while the sliding shoes are movable in the vertical direction with respect to said auxiliary sliding shoe.
It is very advantageous thereby if the sliding shoes are connected to said auxiliary sliding shoe via a flexible connecting element, while the spring members slidably engage said sliding shoes, at a least in a longitudinal direction, wherein said connecting element, which is pressure-rigid, at least substantially extends in the longitudinal direction in the mounted position of the closing element.
In this manner, the spring loading function of the spring members of the sliding shoes is separated from the connecting function, which is performed by connecting elements in this embodiment. Said connecting elements extend at least approximately in the direction of movement of the sliding shoes, and as a result exert a pushing force in the direction of movement on the respective leading sliding shoes. Said longitudinally extending connection furthermore ensures that compression of the sliding shoe will cause hardly any movement of the sliding shoe in the longitudinal direction with respect to the closing element. As a result, slanting of the closing element and of the leading sliding shoes will have less influence on the amount of friction of the sliding shoes in the guide rail grooves, thus ensuring a more constant resistance against movement of the closing element. This leads to greater evenness of movement of the closing element. In an alternative embodiment, said means may be accommodated in the spring members, in such a manner that the sliding shoes can pivot against a spring force from the spring members about a transverse axis of the open roof construction, while the associated sliding shoe occupies a slanting position with respect to the guide groove in the unloaded condition of the respective spring member.
Any play in the vertical direction of the guide groove is thus eliminated in that each sliding shoe is loaded about a transverse axis to a position in which each sliding shoe abuts against the respective wall of the guide groove, at least near the ends, on the upper side and the lower side. This condition exists if each sliding shoe is sufficiently long. The diagonal of each sliding shoe must at least be equal to the height of the guide groove, but preferably the length of the sliding shoes is equal to the height of the guide groove, because in that case there will be no risk of the sliding shoes getting wedged in the guide groove upon pivoting thereon.
It is advantageous when the respective sliding shoes and spring members cooperate in such a manner that the sliding shoe associated with a particular spring member extends obliquely, for example at an angle of a few degrees, such as 3xc2x0, with respect to the guide groove in the unloaded condition of the spring member.
In this manner, the spring members will be loaded by placing the sliding shoes into the guide groove, whereby the sliding shoes must be bent back to a more or less straight position, so that a spring load is effected. The shape of the sliding shoes can be selected such that when the sliding shoes are placed into the guide grooves under spring load, a desired area of the sliding shoes will abut against the guide groove.
Preferably, each spring member is made up of a leaf spring, which is twisted through an angle, preferably of at least approximately 90xc2x0, in a point located between its ends.
In this manner, a spring action in two directions can be obtained by using very simple means. It is very advantageous thereby that each spring member can be rigidly attached to the lower closing element via a snap connection at one end. As a result of this, the sliding shoes and the spring members can be mounted on the lower closing element very easily, while also the mounting of the lower closing element in the frame of the open roof construction is simple, because all the parts are fixedly connected to the lower closing element.
Other alternatives and further elaborations constitute the subject matter of further independent and dependent claims.